Do you just have the PCMCIA card from Verizon? If you do then the only adapter that would work would be the USB v-phone, or you could simply use a softphone. Either of those options pretty much rule out using this as a fax line. Also, some wireless services will not provide a stable, fast enough connection to successfully use Voip communication. Before you purchase this device it would be wise to run the following two tests posting the results here so we can tell you if it is possible to use your connection for Vonage:

Verizon wireless internet gives you a PCMCIA card. It is basically a cell phone on a PCMCIA card that dials in to the Verizon cell towers and gives you service 'wirelessly' over their cell signal. It works the same way plugging a cell into your computer would. Thus, there is no way to use a wireless access point with this setup, as it is not wireless as you would normally have.